What actually kill us when we die?

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Субтитры (27)

0:00Every single cause of death out there actually kills us by interfering with our ability to

0:05produce ATP, - our body’s energy source - powering down the very processes that keep us alive.

0:11It takes two ingredients to make ATP: fuel and oxygen… without enough of either one, your cells

0:18can’t produce enough ATP to keep you alive. Starvation, for instance, is a matter of not

0:23having enough fuel to convert into ATP. But cells are really good at scavenging our bodies’ stores

0:29of fat, protein, and carbs, so in most causes of death, fuel isn’t the limiting factor… oxygen is.

0:36Normally, our respiratory system grabs oxygen from the air, then our circulatory system

0:41shuttles it to various organs, where cells use it to make ATP. Most causes

0:45of death interrupt this journey in some way. Some mess with the initial oxygen-acquiring part;

0:52like, pneumonia fills the lungs with fluid, preventing oxygen from making it into the

0:56bloodstream in the first place. Other respiratory problems, like lung cancer, anaphylaxis,

1:01and drowning, also prevent the respiratory system from effectively grabbing oxygen from the air.

1:06Most causes of death, though, interfere with the second part of the oxygen pathway. Like

1:12heart disease, the most common cause of death worldwide, narrows the arteries, restricting

1:16the flow of blood throughout the rest of the body. Electrocution messes with the electrical

1:21signals that regulate the pumping of the various chambers of the heart, leaving them unable to

1:25effectively pump blood. Strokes – another major cause of death – happen when blood can’t reach

1:31the brain. And sudden trauma can cause so much blood loss that the pressure in the circulatory

1:36system drops, leaving it unable to move blood through the body. In each of these cases,

1:41even though enough oxygen has made it into the body, that oxygen isn’t getting carried

1:45to cells, where it’s needed to produce ATP. And in a few especially-weird causes of death,

1:52plenty of oxygen is making it into the body AND getting where it needs to go, but cells can’t

1:57use it. Cyanide, for instance, messes with the cellular machinery that makes ATP, leaving it

2:03unable to use oxygen to complete the reaction. There are a ton of ways to interfere with the

2:09ATP production pathway – that’s why there are so many so-called “causes of death”.

2:14But no matter where – or how – the pathway fails, the ultimate result is the same:

2:19your body can’t produce enough energy to carry out the processes needed to actually maintain life.